JP2000224927A - Insect-repelling sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an insert-repelling, lightweight and soft sheet which comprises a nonwoven fabric having a specific fineness, a specific METSUKE and a specific air permeability, has a light-transmitting property for obtaining sunlight necessary for the growth of crops, substantially enables the formation of anthocyanin-based pigments and the pollination actions of insects, and has an excellent heat-retaining property, an excellent wind-preventing property or the like, and an excellent insect-repelling property. SOLUTION: This nonwoven fabric-like, insect-repelling sheet comprises heat-adhesive fibers containing a UV absorber and having a fiber fineness of 1-500 dtex in an amount of 0.7-15 wt.% in the fibers, and has a METSUKE of 10-200 g/m2 and an air permeability of >=100 cc/cm2.sec. Therein, the UV absorber preferably comprises at least one UV absorber selected from the group consisting of benzothiazole-based UV absorbers, benzophenone-based UV absorbers, benzoate-based UV absorbers, salicylate-based UV absorbers and cyanoacrylate-based UV absorbers.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention
While having translucency to obtain the solar radiation necessary for growing crops, it has excellent heat retention and windproof properties, has excellent insect repellency due to pest repellency, and develops colors such as anthocyanin pigments in plants. The present invention relates to a non-woven insect repellent sheet, which is adjustable as well as substantially capable of pollinating insects and has good air permeability, and is also suitable as a covering material for greenhouse horticulture.

[0002]

2. Description of the Related Art In agricultural production, protecting crops from insect pests has been a problem that has continued since ancient times. In this pest control, insecticide and natural enemies kill insects, prevent infestation of insects by covering materials, eliminate harmful insects,
The use of inducing effects is one example of control, but the spread of pesticides has drastically reduced the insect damage of crops, which has greatly increased the yield. On the other hand, agriculture workers suffered burns,
It caused problems such as pesticide residue damage to consumers and ecological destruction to the environment. For this reason, the development of low-risk or harmless drugs for the human body and the environment has been promoted. However, when using such agricultural chemicals or the like, operations such as spraying and fumigation are required, and these operations impose a great burden on agricultural producers. The long-term effects of drugs that are currently considered harmless have not been elucidated.

[0003] In addition, there is a growing awareness of health, and there is a movement of consumers seeking organic pesticide-free or low-pesticide agricultural crops, so that there is a demand for insect pest control measures that do not rely only on conventional pesticides of the insecticidal type. As a conventional countermeasure against insect pests without using pesticides of the insecticide type, in addition to the use of natural enemies, the prevention of the propagation of pests by the use of sex pheromones of pests (Japanese Unexamined Patent Publication No.
No. 192024, Japanese Unexamined Patent Publication No. Hei 10-87408), some of which have already been carried out, such as creation of crops resistant to insect damage using genes, and those of research stage, but the target pests are limited. There is no satisfactory way. One of the measures against insect damage that does not use pesticides is a method using a covering material. These covering materials are used for so-called greenhouse horticulture using a house, a tunnel, or the like, and by covering them, pests are prevented from entering the facility. As these coating materials, agricultural films, nets and nonwoven fabrics are widely used.

[0004] Among these, agricultural film is a coating material whose main purpose is to keep heat and keep out rain, and is not air-permeable. In a high temperature period when pest activity is active, the inside of the facility becomes stuffy and requires ventilation. For this reason, as a result of the coating being opened, pests invade and cannot be used alone for insect pest control except during the cold season. In addition, a method of preventing insect damage by coating an agricultural film substantially blocking transmission of light having a wavelength of 380 nm or less by kneading an ultraviolet absorber or the like and cultivating a crop under the film is known. (Japanese Patent Laid-Open No. 54-9
7273). This method is an insect repellent method that cuts off ultraviolet rays in sunlight that strikes a crop, thereby inhibiting the activity of pests in the facility and preventing propagation, and suppressing the invasion of pests from outside the facility.

The above-mentioned agricultural film is used as an ultraviolet cut film for cultivation of leafy vegetables and the like, but it is necessary to form an anthocyanin-based pigment. In plants such as flowers that give blossoms, they cannot be used because the formation of this pigment is hindered by the removal of ultraviolet light, and even when used for cultivation of soft vegetables, the leaf color tends to be hardly dark green. In addition, when pollination is performed using honeybees or bumblebees, the applications are limited, for example, because ultraviolet ray cut films cannot be used because they inhibit the activity of these insects. As a material for the agricultural film, a thermoplastic resin such as a vinyl chloride resin or a polyolefin resin is used. In order to suppress the deterioration of the thermoplastic resin and improve the durability as an agricultural film, it has been widely used to add an ultraviolet absorber to the thermoplastic resin as a weather-resistant stabilizer, but the amount added is small. Usually, when the content is less than 0.1% by weight, the function as an ultraviolet cut film cannot be expected.

As the net, a net using a fiber thread having excellent strength is preferably used as a covering material for preventing insect damage. Since the net has good air permeability, it is used as an insect repellent net especially in summer when the outside temperature is high. ing. In general, the performance of insect-controlling nets is determined by the size (measures) of the gaps created by the yarns constituting the net, but in order to impart pest repellency, metal-deposited films such as aluminum-deposited films Numerous insect-control nets have been developed.

[0007] However, in the case of conventional insect-proof nets, this mesh is often not fixed, and the yarn moves in the process of wind and rain or handling, causing a "misalignment" in which the mesh changes. Insects often entered the area from where the eyes spread. As the insect net using a metal-deposited film, an insect net using an aluminum-deposited film is generally used. This kind of net has excellent pest repellency due to the glittery feeling of the aluminum deposited film, but rain, moisture, chemicals, sprinkling etc during spreading, aluminum deposited part undergoes chemical change to aluminum hydroxide, Since the luster was lost, it could not withstand use at an early stage. In addition, the use of an auxiliary material such as an aluminum vapor-deposited film increases the weight of the net itself, which may cause a high load to be applied to the house or equipment to be spread.

[0008] Nonwoven fabrics are used as materials for lining and materials for lining such as houses. In recent years, the demand for materials for lining is rapidly increasing. The material for bedding is
Unlike agricultural films and nets, this material is mainly used to cover crops directly in open-field cultivation, tunnel cultivation, and house cultivation, and is used for the purpose of heat insulation (prevention of cold and frost damage), wind protection, insect control, etc. . However, the nonwoven fabric for sticking is not only a function of heat retention, windproof, insect repellent, etc. It is necessary to be lightweight and flexible so as not to damage the soil, and to have a light-transmitting property for obtaining solar radiation necessary for growing a crop.

[0009] As a result, the conventional nonwoven fabric for covering is mainly a nonwoven fabric having a small basis weight using fibers having a small fineness. As a conventional nonwoven fabric for covering, the basis weight of polypropylene or polyester is 15 to 25 g /
long-fiber nonwoven fabric of m ^2, and the polyvinyl alcohol or polyethylene having a basis weight of a material 35~55g / m ²
In particular, the demand for long-fiber nonwoven fabrics has been increasing significantly. For this reason, the conventional nonwoven for covering is low in strength and there is a difference in hygroscopicity due to the difference in material, such as pests invading through widened gaps,
Insect repellency was insufficient. In addition, it is widely used to add a UV absorber as a weathering stabilizer in order to suppress deterioration of the resin used as a material for the nonwoven fabric for covering and improve durability, but the amount of addition is small. Usually, it is less than 0.5% by weight, and the function as an insect repellent material cannot be expected.

[0010]

DISCLOSURE OF THE INVENTION The present invention is lightweight and flexible, has a light-transmitting property for obtaining solar radiation necessary for growing crops, and substantially forms anthocyanin pigments and pollinates insects. It is possible to provide a non-woven insect repellent sheet which is excellent in heat insulation and wind resistance, has excellent insect repellency due to insect repellency, and is also excellent as a covering material for greenhouse horticulture such as a material for sticking. Make it an issue.

[0011]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies in order to solve the above-mentioned problems of the prior art, and as a result, made a fiber containing a large amount of an ultraviolet absorber into a non-woven insect repellent sheet, and under the covering, By cultivating the crop, the amount of ultraviolet rays can be controlled, so that the crops can be exposed to the necessary ultraviolet rays, the degree of color development of anthocyanin pigments and the like can be adjusted, and the pollination of insects is virtually possible. In addition, the present inventors have found an excellent new finding that they can also impart pest repellency, and have completed the present invention.

That is, the present invention has the following configuration. (1) An insect-proof sheet in the form of a nonwoven fabric made of a heat-adhesive fiber having an ultraviolet absorber in a fiber content of 0.7 to 15% by weight and a fineness of 1 to 500 dtex, having a basis weight of 10 to 20.
An insect-proof sheet in the form of a nonwoven fabric having 0 g / m ² and air permeability of 100 cc / cm ² · sec or more. (2) The insect repellent sheet according to (1), wherein the ultraviolet absorber is at least one selected from the group consisting of benzotriazole-based, benzophenone-based, benzoate-based, salicylate-based, and cyanoacrylate-based ultraviolet absorbers. (3) The insect-proof sheet according to (1) or (2), wherein the heat-adhesive fiber is a heat-adhesive conjugate fiber composed of a low-melting resin having a melting point difference of 10 ° C. or more and a high-melting resin. (4) The insect-proof sheet according to any one of (1) to (3), wherein the heat-adhesive fiber is a long fiber.

[0013]

Embodiments of the present invention will be described below. In the insect repellent sheet of the present invention, the fibers constituting the insect repellent sheet are fibers containing an ultraviolet absorbent in an amount of 0.7 to 15% by weight, more preferably 1 to 12% by weight. When the ultraviolet absorbent content of the fiber is less than 0.7% by weight, the insect repellent sheet may have an insufficient insect repellent effect. Further, when the content of the ultraviolet absorber in the fiber greatly exceeds 15% by weight, the concentration of the ultraviolet absorber in the fiber becomes uneven, and the fiber properties such as strength, elongation and heat shrinkage become uneven. There is.

In the insect repellent sheet of the present invention, the ultraviolet absorber which can be contained in the fibers constituting the insect repellent sheet is a drug having a property of absorbing light having a wavelength of 400 nm or less. The ultraviolet absorber is preferably selected from the group consisting of benzotriazole, benzophenone, benzoate, salicylate and cyanoacrylate ultraviolet absorbers. These ultraviolet absorbers may be used alone, or two or more of them may be used in combination in view of the effects of the combination. Examples of the above-mentioned various ultraviolet absorbers are shown below, but the present invention is not limited thereto.

As the benzotriazole type ultraviolet absorber, 2 (2'-hydroxy-5-methylphenyl) benzotriazole, 2 (2'-hydroxy-3'-t-butyl-5'-methylphenyl) -5- Chlorobenzotriazole can be mentioned. Examples of the benzophenone-based ultraviolet absorber include 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone,
-Hydroxy-4-octoxybenzophenone and 2-hydroxy-4-dodecyloxybenzophenone. Benzoate UV absorbers include:
2,4-di-t-butyl-phenyl-3,5-di-t-
Butyl-4-hydroxybenzoate can be mentioned. Phenyl salicylate, pt-butylphenyl salicylate,
p-octylphenyl salicylate can be mentioned. As the cyanoacrylate-based ultraviolet absorber, 2-
Ethylhexyl-2-cyano-3,3'-diphenylacrylate can be mentioned.

The fineness of the fibers constituting the insect repellent sheet of the present invention is 1 to 500 dtex, preferably 1 to 250 dte.
x. When the fineness is less than 1 dtex, the absolute amount of the ultraviolet absorbent per fiber becomes small, so that it may be difficult to maintain the insect repellent effect for a long time. Also,
The fiber may be deformed when the fiber is made into a nonwoven fabric, or may be broken when a sheet having a small basis weight is formed. Fineness is 50
If it exceeds 0 dtex, the rigidity of the insect repellent sheet may be increased and workability may be deteriorated, the weight may be increased, transportation may be inconvenient, and a large load may be applied to the spread portion to damage facilities such as a house.

In the insect-proof sheet of the present invention, the fibers constituting the insect-proof sheet are heat-adhesive fibers, and the heat-adhesive fibers include regular fibers made of a single component resin and composite fibers made of a plurality of resins. I can do it.

In the insect-proof sheet of the present invention, in order that the intersections of the heat-adhesive fibers constituting the insect-proof sheet are heat-bonded and sufficiently fixed, a heat-adhesive conjugate fiber is preferably used as the heat-adhesive fiber. Here, the heat adhesive composite fiber is
A bicomponent or higher composite fiber comprising a low melting point resin and a high melting point resin having a melting point difference of at least 10 ° C. and having a low melting point component formed continuously on at least a part of the fiber surface. As the composite structure of the composite fiber, for example, any of a sheath-core type, a side-by-side type, a sea-island type and the like can be used.

Examples of the low-melting resin and high-melting resin which are the raw materials of the heat-adhesive conjugate fiber include high-density polyethylene, low-density polyethylene, linear polyethylene, polypropylene, polyethylene terephthalate, and polyamide, and particularly preferably polyolefin. is there. Examples of combinations of heat-adhesive conjugate fibers include high density polyethylene / polypropylene, linear low density polyethylene / polypropylene, low density polyethylene / polypropylene, binary copolymers or ternary copolymers of propylene with other α-olefins. Coalesced / polypropylene, linear low-density polyethylene / high-density polyethylene, low-density polyethylene / high-density polyethylene, various polyethylenes / polyethylene terephthalates, polypropylene / polyethylene terephthalate, binary copolymers of propylene and other α-olefins or terpolymers Original copolymer / polyethylene terephthalate, low melting point thermoplastic polyester / polyethylene terephthalate, various polyethylene / nylon 6, polypropylene / nylon 6, binary copolymer of propylene and other α-olefin or Terpolymer / nylon 6, nylon 6
/ Nylon 66, nylon 6 / thermoplastic polyester and the like.

Among these, a combination of polyolefins or a combination of polyolefin and polyester is preferable. Specific examples thereof include high density polyethylene / polypropylene, ethylene / propylene / butene-1 terpolymer / polypropylene, and ethylene / propylene binary. Copolymer / polypropylene, ethylene / propylene / butene-1 terpolymer / polyethylene terephthalate,
Alternatively, high-density polyethylene / polyethylene terephthalate and the like can be mentioned. Further, among these, polyolefins such as high-density polyethylene / polypropylene, ethylene / propylene / butene-1 terpolymer / polypropylene, and ethylene / propylene binary copolymer / polypropylene are particularly preferred from the viewpoint of chemical resistance. preferable.

An ultraviolet absorber is added to the heat-adhesive conjugate fiber at 0.7.
In order to make the heat-adhesive conjugate fiber contained, it may be contained in any one of the low-melting-point resin and the high-melting-point resin, or may be contained in a plurality of kinds of resins.
When it is contained in plural kinds of resins, the content may be changed depending on the resin. When the heat-adhesive composite fiber has a sheath-core structure,
The ultraviolet absorber may be contained in the sheath component, the core component, or both. The insect repellent sheet of the present invention may contain the above-mentioned ultraviolet absorber, and may further contain a stabilizer, a flame retardant, an antibacterial agent, a coloring agent, and the like as long as the effects of the present invention are not hindered.

In the present invention, JIS L 1021
The thickness of the insect repellent sheet measured according to the "test method for fiber floor covering structure" is preferably in the range of 0.1 to 5 mm. If the thickness of the insect repellent sheet is less than 0.1 mm, tearing may occur, and if it exceeds 5 mm, the air permeability deteriorates, and when the insect repellent sheet is spread on a house or the like and a crop is cultivated therein, The crop may be damaged by stuffiness. Further, as the thickness increases, the light-shielding property also increases, so that sufficient sunlight for growing crops cannot be obtained. The thickness is appropriately determined depending on the intended use, crops, types of pests, and the like.

The insect repellent sheet of the present invention has a basis weight of 10 to 200.
g / m ² . Since the weight is smaller as the basis weight is smaller, the workability and workability in the case of spreading in a house and the like are improved, but at the same time, the strength of the insect repellent sheet is reduced,
It is easy to tear. If the basis weight is much less than 10 g / m ² , besides the decrease in strength, the spots are likely to occur,
In some cases, it cannot be used as an insect repellent sheet. If the basis weight greatly exceeds 200 g / m ² , not only workability and workability in the case of spreading in a house, etc., are deteriorated,
It is also unsuitable as an insect repellent sheet because it also blocks sunlight required for plants.

The air permeability of the insect repellent sheet of the present invention is 100 c
c / cm ² · sec or more. Here, the air permeability is J
This is the amount of air passing through the test piece measured according to the method described in the section on air permeability of IS L 1018 “Knitted fabric test method”. The higher the air permeability, the better the ventilation, and when the insect repellent sheet is spread on a house or the like and a crop is cultivated therein, stuffiness is less likely to occur. 1 air permeability
If it is less than 00 cc / cm ² · sec, ventilation may be poor and stuffiness may occur.

The insect repellent sheet of the present invention is formed by forming the heat-adhesive fiber into a web having a desired basis weight, and simultaneously or after forming the web, the web is heated to a temperature at which the intersections of the heat-adhesive fibers are heat-bonded. The nonwoven fabric insect-proof sheet obtained by heating at the intersections by heating as described above. The shape of the web for obtaining the insect-proof sheet of the present invention may be a long fiber web shape in which long fibers are laminated, such as a spun bond method or a melt blow method, or the long fibers may be cut to an arbitrary length. Thereafter, a short fiber web shape obtained by laminating these using a card machine or a random webber may be used. Generally, in order to obtain an insect repellent sheet having a small basis weight and a light weight, and having a low light-shielding effect in order to obtain the sunlight required for plants, a spun bond method or a melt blow method is used. Is required, a spun bond method is particularly preferably used. When it is necessary to increase the thickness of the insect repellent sheet or to increase the basis weight, a card method or the like is preferably used for forming the web. The method of creating a web does not define the present invention at all.

Examples of a device for heating the intersections of the above-mentioned heat-bondable fibers and thermally bonding the same include, for example, a hot-air heater, an infrared heater, a far-infrared heater, a high-pressure steam heater,
Examples include an ultrasonic heating machine, a hot roll heating machine, a thermocompression roll heating machine, an embossing roll thermocompression machine, a through air heating machine, and a heat treatment apparatus combining a plurality of these.

[0027]

The present invention will be described in more detail with reference to the following examples. The test method according to the present invention will be described.

(Thickness) It complies with JIS L 1021 “Test method for structure of fiber floor covering”.

(Ultraviolet transmittance) Using a spectrophotometer (Model UV2100, manufactured by Shimadzu Corporation), a wavelength of 280 to 380 nm
Was measured every 20 nm, and the average of these measured values was defined as the ultraviolet transmittance. A high ultraviolet transmittance is advantageous for the formation of anthocyanin pigments in crops and for flower visiting activities such as bees, but the pest repellent effect is reduced.
Conversely, if the ultraviolet transmittance is low, the effect of repelling pests increases, but it is disadvantageous for the formation of an anthocyanin-based pigment.

(Air permeability) The air permeability conforms to 6.34 air permeability section of JIS L 1018 "Knitted fabric test method". For the measurement, a woven fabric air permeability tester manufactured by Toyo Seiki Seisaku-sho, Ltd. was used.

EXAMPLE 1 An ethylene / propylene / butene-1 terpolymer having a melting point of 133 ° C. was used as a sheath component, and polypropylene having a melting point of 162 ° C. was used as a core component. % By weight / 50% by weight, fineness: 20 dtex, fiber length: 1
A short fiber web having a basis weight of 197 g / m ² was prepared by a card method using a 28 mm sheath-core type heat-adhesive conjugate fiber.
The heat-adhesive conjugate fiber had 10% by weight of 2 (2'-hydroxy-5-methylphenyl) benzotriazole as a sheath component and 2 (2'-hydroxy-5-methyl) as a core component as an ultraviolet absorber. 10% by weight of phenyl) benzotriazole and 10% by weight of the whole fiber were added. This web is heat-treated at 150 ° C. using a hot-air heater,
The intersection of the heat-adhesive conjugate fibers was heat-bonded at a thickness of 3.7.
mm nonwoven fabric sheet sample was obtained. Using this nonwoven sheet sample, the air permeability and the ultraviolet transmittance were measured.
Table 1 shows the results.

EXAMPLE 2 A high density polyethylene having a melting point of 131 ° C. was used as a sheath component, and a polypropylene having a melting point of 162 ° C. was used as a core component.
The composition ratio of the core component is 50% by weight / 50% by weight, and the fineness is 10
A nonwoven fabric sheet sample composed of dtex heat-adhesive composite long fiber yarn was prepared by a spun bond method. This nonwoven fabric sheet sample was a nonwoven fabric sheet sample having a basis weight of 20 g / m ² and a thickness of 0.2 mm, which was thermocompression-bonded with an embossing roll having a temperature of 125 ° C. and a convex area of 14%. In the heat-bonding and fusible composite filament yarn, 10% by weight of 2 (2'-hydroxy-5-methylphenyl) benzotriazole was used as a sheath component and 2 (2'-hydroxy- 5-methylphenyl) benzotriazole in 1
0% by weight and 10% by weight as a whole fiber were added. Using this nonwoven sheet sample, the air permeability and the ultraviolet transmittance were measured. Table 1 shows the results.

Example 3 Using a high-density polyethylene having a melting point of 133 ° C. as a sheath component and polypropylene having a melting point of 166 ° C. as a core component,
A short fiber web having a basis weight of 118 g / m ² by a card method using a sheath-core heat-adhesive conjugate fiber having a fineness of 2 dtex and a fiber length of 128 mm having a core component composition ratio of 40% by weight / 60% by weight. Created. In addition, the heat-adhesive conjugate fiber includes
As an ultraviolet absorber, 2 (2′-hydroxy-
1.2% by weight of 5-methylphenyl) benzotriazole, 0.6% by weight of 2 (2'-hydroxy-5-methylphenyl) benzotriazole as a core component, and 0.84% by weight of the whole fiber were added. The web was heat-treated at 155 ° C. using a hot-air heater to obtain a 1.9 mm-thick nonwoven sheet sample in which the intersections of the heat-adhesive conjugate fibers were heat-bonded. Using this nonwoven sheet sample, the air permeability and the ultraviolet transmittance were measured. Table 1 shows the results.

Example 4 A high density polyethylene having a melting point of 134 ° C. was used as a sheath component, and a polypropylene having a melting point of 166 ° C. was used as a core component.
A short fiber web having a basis weight of 183 g / m ² by a card method using a sheath-core type heat-adhesive composite fiber having a fiber length of 64 mm and a fineness of 500 dtex having a composition ratio of a core component of 50% by weight / 50% by weight. Created. The heat-adhesive conjugate fiber had 2% by weight of 2 (2'-hydroxy-5-methylphenyl) benzotriazole as a sheath component and 28% by weight of 2,4-dihydroxybenzophenone as a core component as an ultraviolet absorber. %, And 15% by weight as a whole fiber. This web is heat-treated at 155 ° C. using a hot-air heater,
The point of intersection between the heat-adhesive conjugate fibers is heat-bonded, and the thickness is 4.8 m.
m of the nonwoven fabric sheet sample was obtained. Using this nonwoven fabric sheet sample, the air permeability and ultraviolet transmittance were measured and evaluated. Table 1 shows the results.

Comparative Example 1 A short fiber web having a basis weight of 433 g / m ² was prepared by the card method using the same heat-adhesive conjugate fiber as in Example 1. In the heat-adhesive conjugate fiber, 2 (2'-hydroxy-5-methylphenyl) benzotriazole was used as a sheath component in an amount of 0.2% by weight as an ultraviolet absorber, and 2 (2'-
0.2% by weight of (hydroxy-5-methylphenyl) benzotriazole was added, and 0.2% by weight of the whole fiber was added. This web was heat-treated in the same manner as in Example 1 to obtain a nonwoven fabric sheet sample having a thickness of 8 mm. However,
This nonwoven fabric sheet sample was poor in handleability due to its thickness, and did not transmit much sunlight necessary for growing plants. Therefore, it was unsuitable as an insect repellent sheet.

COMPARATIVE EXAMPLE 2 An ethylene / propylene binary copolymer having a melting point of 134 ° C. was used for the sheath component, and polypropylene having a melting point of 165 ° C. was used for the core component. The composition ratio of the sheath component / core component was 50% by weight / 50. Using a heat-adhesive conjugate fiber having a fiber length of 128 mm and a fineness of 0.5 dtex, which is a weight%, and having a basis weight of 440 g by a card method.
/ M ² short fiber web was prepared. The heat-adhesive conjugate fiber had 0.2% by weight of 2 (2'-hydroxy-5-methylphenyl) benzotriazole as a sheath component and 2 (2'-hydroxy- 5-
0.2% by weight of methylphenyl) benzotriazole,
0.2% by weight of the whole fiber was added. This web was heat-treated in the same manner as in Example 1 to obtain a nonwoven fabric sheet sample having a thickness of 1 mm. Using this non-woven sheet sample,
The air permeability and ultraviolet transmittance were measured. Table 1 shows the results.
This nonwoven fabric sheet sample had poor air permeability because the fibers were in a very dense state, and did not transmit much light necessary for growing plants. Therefore, it was unsuitable as an insect repellent sheet.

Comparative Example 3 A short fiber web having a basis weight of 7 g / m ² was prepared by a card method using the same heat-adhesive conjugate fiber as in Comparative Example 2. However, a uniform web was not able to be obtained because there were many spots in the basis weight. Therefore, it was unsuitable as an insect repellent sheet.

Comparative Example 4 An ethylene / propylene / butene-1 terpolymer having a melting point of 133 ° C. was used as a sheath component, and a polypropylene having a melting point of 162 ° C. was used as a core component. Fiber length 64 mm, fineness 750% by weight / 50% by weight
A short fiber web having a basis weight of 189 g / m ² was prepared by a card method using the dtex sheath-core type heat-adhesive conjugate fiber.
The heat-adhesive conjugate fiber had 0.2% by weight of 2 (2'-hydroxy-5-methylphenyl) benzotriazole as a sheath component and 2 (2'-
0.2% by weight of (hydroxy-5-methylphenyl) benzotriazole was added, and 0.2% by weight of the whole fiber was added. This web was heat-treated at 150 ° C. using a hot-air heater to obtain a 6.1-mm-thick nonwoven sheet sample in which the intersections of the heat-adhesive conjugate fibers were heat-bonded. Using this nonwoven sheet sample, the air permeability and the ultraviolet transmittance were measured. Table 1 shows the results. This nonwoven fabric sheet sample had a large fineness and the degree of fiber accumulation was very coarse. Also, because the amount of UV absorber added is small,
UV light was transmitted. Therefore, it was unsuitable as an insect repellent sheet.

Examples 5 and 6 (Pest repellent test) Two strawberries (variety: Toyoka) cultivated in a pot and attached with flowers and fruits were grown 30 cm in length and 30 cm in width.
The sample was placed in a rectangular iron frame having a height of 40 cm, and the nonwoven fabric sheet samples obtained in Examples 1 and 2 were stretched around the iron frame (Examples 5 and 6). In consideration of the influence of breakage during use, the nonwoven fabric sheet sample had a width of 5 cm and a maximum opening length of a crack of 5 cm.
An opening of about mm was provided at an arbitrary height, one at each of four sides. 50 citrus thrips, a strawberry pest, were released around this and left for 48 hours. Forty-eight hours later, the number of Thrips palmi invaded into the iron frame was counted. In the test, solar radiation close to natural light was obtained, and
The test was performed in a sunny glass room so that the pests did not escape, and after the test the pests were killed. Table 2 shows the results. In both the nonwoven sheet samples, Example 5 did not show any penetration. In the sixth embodiment,
Only three were invaded. Therefore, favorable pest repellency was confirmed.

Comparative Examples 5 and 6 In the nonwoven sheet samples of Examples 1 and 2, the amount of the ultraviolet absorber added was 0.2% by weight for both the sheath and core components, and the total amount of the fibers was 0.2% by weight. Samples (Comparative Examples 5 and 6) were prepared, and the same tests as in Example 5 were performed. Table 2 shows the results. In both samples, the infestation of the insect pest, Thrips palmi Karny, was observed. In particular, in the sample of Comparative Example 6, as many as 34 horses were invaded, and no pest repellency was observed.

In the above Examples and Comparative Examples, benzotriazole-based and benzophenone-based UV absorbers were used as UV absorbers, but the same effect can be expected with benzoate-based, salicylate-based, and cyanoacrylate-based UV absorbers. can do. Since the insect repellent sheet of the present invention has excellent pest repellency, it can be used not only as an insect repellent sheet for agriculture but also for construction, home use, and many other uses. Further, the insect repellent sheet of the present invention can be used in combination with many other materials such as fabrics, films, metal nets, construction materials, civil engineering materials, and agricultural materials.

[0042]

[Table 1]

[0043]

[Table 2]

[0044]

The insect repellent sheet of the present invention suppresses pest invasion into crops and inhibits the formation of anthocyanin pigments in crops by using thermoadhesive fibers containing a large amount of an ultraviolet absorber. In addition, the insect repellent sheet is a nonwoven fabric that is substantially capable of pollinating insects and is also suitable as a covering material for greenhouse horticulture.

Claims (4)

[Claims] 1. A non-woven insect repellent sheet comprising a heat-adhesive fiber having an ultraviolet absorber in a fiber content of 0.7 to 15% by weight and a fineness of 1 to 500 dtex, having a basis weight of 10%.
~ 200 g / m ² , air permeability 100cc / cm ² · sec
The above-mentioned insect-proof sheet in the form of a nonwoven fabric. 2. A benzotriazole-based ultraviolet absorber,
The insect repellent sheet according to claim 1, which is at least one member selected from the group consisting of a benzophenone-based, benzoate-based, salicylate-based, and cyanoacrylate-based ultraviolet absorber. 3. The insect-proof sheet according to claim 1, wherein the heat-adhesive fiber is a heat-adhesive conjugate fiber comprising a low-melting resin having a melting point difference of 10 ° C. or more and a high-melting resin. 4. The heat-adhesive fiber is a long fiber.
3. The insect repellent sheet according to any one of 3.